The morma peters co



(No Model) 7 QSheets-Sheet 1.

F. BUCHTER.

MAGHINE'POR MAKING TWIST DRILLS. No. 320,456. Patented Juile 23,1885.

- (No Model.) 4 Sheets-Sheet 2.

F. BUGHTER.

MACHINE FOR MAKING TWIST DRILLS.

No. 320,456. Patented June 23. 1885.

75. 2 WITNESSES,- INVENTEJF; gwwjw 09M Amman (No ModeL) 4 Sheets-Shet 3.F. BUCHTER.

MACHINE FOR MAKING TWIST DRILLS.

No. 320,456. Patented June 23, 1885.

i K a a l I O THE uonms PETER 00.. Pucnouwa, WASHINGTON n c (No Model.)

' 4 Sheets-Sheet 4. F.,BUIGHTER. MACHINE FOR MAKING TWIST DRILLS.

Patented June 23, 1885.

TE. El-

Tu: mm: mans co. mo'ro-umo wAsmuaron n c UNITED STATES PATENT OFFICE.

FRANK BUCHTER, OF NEW BEDFORD, MASSACHUSETTS, ASSIGNOR TO THE MORSETWIST DRILL AND MACHINE COMPANY, OF SAME PLACE. 1

MACHINE FOR MAKING TWIST-DRILLS.

SPECIFICATION forming part of Letters Patent No. 320,456, dated June 23,1885.

Q Application filed March 18,1885. (No model.)

' In machines of this class, in which the drill-' blank is carriedforward-androtated while operated upon by fixed cutters, there are threemotions to be imparted to the drill blank. Therfirst of these is aregular-or constant forward motion past'thecutter; the second is therotationof the drill-blank while passing the cutter, and the third isthe gradual and regulated increase of forward motion of the rotatingdrill-blank, this last being required to obtain what is known as] the increased twist.

My present invention relates to improvements in the devices by whichthese motions are obtained, and also in improvements in thearrangementof the cutters or mills which coact with therest ofthemachine to form the drill.-

In theaecompany'ing drawings, Figure l is a front elevation, 'and Fig. 2aside elevation,

of a machine embodying my presentimprovements, in the form how bestknown to me. Fig. 3 is a top plan view of the same,.an'd Fig. 4a detailof a part ofthe structure, as will be hereinafter explained. Figs. 5 and6 are top plan views of the machine upon the plane of the lines and fly,respectively, in Fig. 1.

I will describe first the mechanism for giving the drill its constantforward motion. a

A represents the main frame of the machine, within which a carriage, B,is arranged to rise and fall, being guided .by grooves,'as' shown inFig. 5. ward motion of the drill-blank is derived from the forward orupward motion of this carriage, and this in turn comes from therevolution of a pair of screws, a a, (best seen'in Fig. 1,) providednear their lower ends with" creased twist.

The regular forward or upis provided with a pulley, C, .(see Figs. 1 andan arm extending from the carriage'B, and this intermediate gear i'sinturn driven by a pinion, q, upon a shaft carrying a gear, Q,whichmesheswith and is driven by a pinion, e, upon asecond verticalshaft',E. This shaft E also carries atv its lower extremity a gear,

F, (see Fig. 6.) meshing with and driven bya gear, f, which in'turntakes its motion from the worm gear-shaft and pulley 00, beforementioned.

The third motion. to be imparted to the d rillblank is thegradually-increased forward mo tion above mentioned. This is obtained bymeans of devices best'shown in Fig. 4, where in, as will be seen, thebases or lower ext-remities of the screw-rods a a are represented asresting uponlevers G, which rest upon and areoperated by cams H.Thepitchof these cams corresponds with the increased or forwardrnovemcntrequired to produce the in- These cams aremountedon a common shaft, h,which is geared to and driven by a depending worm-shaft, I, (see Figs.1 and connection with their drivinggears, (see Fig.

4,) toallow for their upward motion under the influence of the lever G,as described. The pinion c is also splined upon the shaft E to allow forthe forward or upward motion of the carriage B and the train of gearingcarried by The mills or cutters K K are of ordinary construction, andmounted upon. adjustable bearings in the ordinary manner. driven byworm-gearsand shafting of their own, as shown in Figs. 1, 2, and '3.They have, however, one peculiar feature, which I will now describe.Inasmuch as the depth of the grooves in the drill gradually decreasesThey are 5 IOC ions N N, meshing in and driven by a rack,

O. This rack is,for convenience, made in two .parts, centrally pivoted,as shown in Fig. 2,

and so that it may be thrown out of connection'with the pinions N N, ifdesired.

As it is desirable that the motion of the cutters apart to reduce thedepth of the groove in the manner just described should be regulated byand correspond with the gradual advance of the drill-blank, the rack 0may be arranged to be operated by an arm, 1, against which a part of thecarriage B bears. 111 this way, as will be seen, the gradual forward orupward motion of the carriagcB acting against the arm P produces alateral motion of the rack O, and this, by means of the pinions N,screws .1, and sliding carriages L, moves the cutters K apart.

As the whole operation of cutting the grooves of the drill is performedby its passing once upward or forward by the cutters K,

it is obvious that the machine must be driven slowly. With this fact inmind it will be easy to understand the operation of the machine, whichis as follows: The carriage B with its connected parts and the screws aa being at the r lowest point in the machine, the shank of thedrill-blank is inserted in the-sleeve D, and the cutters K K are set atthe proper distance apart to commence their work upon the drill-blank.Power being now applied to the pulley G, and also to the pulleys whichdrive the cutters, the rotation of the screws a a moves the carriage Band carries the drill blank slowly upward or forward past the re volvingcutters, and atthesame time the drillblank is slowly rotated through theagency of the shaft E and its gearing. Simultaneously with theseoperations, the rotation of the cams H H produces an additional forwardor upward movement of the screws a a, and consequentlyof the carriage Band the drill-blank. Moreover, as the carriage B gradually moves forwardor upward, it strikes against and operates the arm P and thus moves therack 0. thereby gradually moving the cutters K K apart as the cuttingprogresses. After-the whole of the drilltblank has passed by thecutters, the forward motion of the machine is stopped, its work havingbeenaccomplished.

The return of the carriage B and screws a a to their original or lowestposition is accomplished by imparting a reverse motion 'to the gearswhich drive them. This is done by means of a hand-wheel, S, upon theupper part of the shaft E, Fig. l, by turning which all the gearing maybe made to operate in the reverse direction. The cutters and theiroperating-rack 0 may also be returned to their original positions bymeans-of hand-wheels B .R operating the screws Z Z. These hand-wheelsare shown in Figs. 1 and 3.

In order to adapt the machine to various sizes of drill, intermediategearing of various sizes may be used inthetrain of gearing employed torotate-the sleeve D; also, the rate of forward motion of the screws a amay be varied for any particular size of drill by chang ing theintermediate gear, 1'. (See Fig. 6.)

I claim- 7 1. In a machine for making twist-drills, the forwardingmechanism for giving an accelerated forward motion to the drill-blankpast the cutters, it-cons'isting in the combination, with theforwardingscrews,of levers which bear against and lift theforwardingscrews, and cams mounted upon a suitable driving-shaft,the'cams being arranged to bear against and lift the levers, allsubstantially as herein set forth.

2. In annachine for making twist-drills, the combination, with a rotarysleeve which carries and rotates-the drill-blank, of a rotating shaft,E, said shaft being connected by intermediatege'aring, substantially asdescribed, both with the drill-rotating sleeve and also with the-mainsource of power of the machine, all substantially as herein set forth,and for the purposes herein specified.

3. In a machine for making twist-drills, the combination, with cuttersarranged to be moved laterally-toward and away from the central line-ofthe drill-blank, of right and left handed screws Z- Z, t-heir pinions NN, and a rack, O 0,-foractuating the pinions, all substantiall y asherein set forth.

4. In a machine for making twist-drills, the combination of the cuttersK, mounted in laterally-movable supports, the screws Z Z, pinions N,rack 0, arm I. and forwardly-moving carriage B, all substantially asherein set forth.

In testimony whereof I have hereunto subscribed'm'y name this 12th dayof March, A.

FRANK BUCHTER. Witnesses:

GEO. R. STE'rsoN, LEMUEL LE B. HOLMES.

